A disturbing new film from Britain’s Channel 4 is making waves in the U.K. and overseas, with video of executions and other war crimes committed during the final five months of Sri Lanka’s 25 year civil war. The army ultimately defeated the rebel Tamil Tigers in May, 2009– but not before an estimated 100,000 people were killed.

Channel 4 said some of the footage has never been seen before and took two years to put together and authenticate.

One of the most graphic parts shows three prisoners who are on their knees, bound and blindfolded, while government soldiers stand over them. One soldier is heard saying, "Is there no one with balls to kill a terrorist?"

"Of course there is, shut up," another soldier says.

Then all three prisoners are shot.

There’s another clip where a soldier laughs after a bound prisoner is gunned down at close range. "It’s like he saw," the soldier says, referring to the executed man. "He looked, then he looked away."

The videos were taken by government troops on their mobile phones as "grotesque war trophies," according to Channel 4.

There’s also footage of a hospital in a rebel-held area that was shelled by government troops over a period of days. A witness interviewed in the film said the hospital was "targeted" and that 10-15 people were killed in the assault.

But it’s not just the government’s troops that are shown committing atrocities. The film includes video of Tamil Tigers firing at civilians trying to escape the conflict zone.

According to the BBC, the British Foreign Office called the film’s content "horrific" and said it would pressure Sri Lanka to investigate. Don’t hold your breath. The government’s response to the film? They called the footage fake and "malicious."